Multiple control switch



8- 1934- E. c. RANEY 1,971,732

MULTIPLE CONTROL swr'rcu Original FiledvApril 29, 1932 2 Sheets-Sheet. 2

Patented Aug. 28, 1934 UNITED STATES MULTIPLE CONTROL SWITCH Estel C. Raney, Columbus, Ohio Original application April 29, 1932, Serial No. 608,319. Divided and, this application May 31,

1934, Serial No. 728,413

9 Claims. (01. 200-83) My invention has for its object to provide a switch particularly adapted for controlling a refrigerating apparatus, means being provided for the manual and overload operation of the switch independent of the automatic operations of the switch induced by the thermic conditions of the refrigerator.

The invention particularly has for its object to produce in such a switch means for causing wider separation of the contacts of the switch when the current in the electric motor that drives the refrigerating apparatus rises in value to a point such as to endanger the motor or the apparatus than is' produced in the normal operation of the motor in actuating the refrigerating apparatus. Thus, if an excess current from any cause is caused to flow in the motor circuit, the construction of the switch is such that the switch will produce an exceedingly wide break. This enables the use of the control device to control refrigerators of different capacities requiring motors of different sizes and using currents of different values, and wherein the movement of the switch contacts may be maintained relatively small in order that the switch may respond with accuracy to the temperature changes of the refrigerator, and yet ample protection will be afforded to a motor of any capacity in case an ab-. normal condition arises.

The invention consists in other features and advantages which will appear from the following description and upon examination of the drawings. Structures containing the invention may partake of different forms and may be varied in their details and still embody the invention. As illustrative of a practical application of the invention, I have selected the multiple control-switch. shown in the drawings and described hereinafter.

' This application is a division of my application Ser. No. 608,319 filed April 29, 1932 for Multiple control switch.

Fig. 1 illustrates a view of a section of the switch and also illustrates diagrammatically a refrigerating system to which the switch may be connected. Fig. 2 is a broken view of the switch illustrated in Fig. 1 and illustrates the location of parts of the switch when opened by an overload current. Fig. 3 illustrates a broken view of actuating parts of the switch. Fig. 4 illustrates latch members that are interrelated to produce wide opening of the switch. Fig. 5 illustrates a top view of a guide plate. Figs. 6, 7, and 8 illustrate the members illustrated in Fig. 4 in perspective. Fig. 6 illustrates a view of a member that is automatically released upon the flow of an overload or excess current in the motor circuit. Fig. 7 illustrates a member that may be manually operated or may be operated by the automatic operation of the member illustrated in Fig. 6. Fig. 8 illustrates a member for disposing the contacts so that they may be operated thermically in response to temperature conditions, or for widely separating the contacts to protect motors of different capacities. v

The multiple control switch illustrated in the drawings is contained within a shell 1., The shell has a face plate or end part 2 through which extend switch control members, convenient for observation and manual manipulation, and a base part 6 for closing the end of the shell. The base 6 and the frame 10 form a support for'parts of the switch. The base is removably connected to the shell by a screw 11 thatextends through the end part 2 of the shell and into the frame 10.

The base 6 is provided with a threaded socket 7 for removably connecting a bellows 12 to the switch. The bellows 12 is located in the cup 13, and the walls of the socket have a screw formation 14 whereby the cup 13 and consequently the bellows may be connected to the base 6 and in position to operate the switch. A pipe 15 is connected to the end of the bellows through the bottom of the cup 13, and the parts are so formed as to enable rotative movements of the cup 13 relative to the pipe and bellows to enable ready connection of the bellows to the base 6.

Replaceability of the bellows renders the switch usable with refrigerators having a variety of capacities by the use of bellows having different sizes, and also it enables the use of bellows having parts for connecting them with the apparatus for direct refrigerant pressure control or indirect pressure control, as bythermic control. A suitable thermic expansible liquid having a low boiling point may be inserted inthe bellows and pipe, and its changes-in pressure due to changes in temperature will operate the bellows. Or if the bellows is connected to the low pressure side of the refrigerating apparatus,-the refrigerant fluid used in the refrigerating apparatus will be introduced into the pipe and the bellows and will vary the volume of the bellows according to the pressure within the part of the apparatus to which the pipe is connected, and consequently substantially according to the temperature of the chilling unit of the refrigerator.

Where the bellows is operated by pressure produced by heat transmission, the pipe 15, may

be closed at its end or it may be connected to a bulb 29. The end of the pipe or the bulb, if a bulb is used, is mounted in the refrigerator in close heat conductive relation with the chilling unit to correspondingly affect the pressure with- 5 in the bellows.

As indicated in Fig. 1, the motor 30 is connected to the switch 31, and the circuit of the motor is opened and closed by the switch, which operated by the bellows 12 when the bellows reaches definite points in its expansion as affected by the temperature of the chilling unit 33. The motor 30 operates the compressor 35 which draws the refrigerant from the chilling unit 33 and forces it into the condenser 36 from which it is directed into the evaporator or chilling unit 33 in the manner well known in the art.

Themovable contact member 37 is insulatingly supported on a jointed switch arm formed of a pair of relatively movable plates 38 and 39. The

plate 39 is spring pressed endwise by the springs 40 against the end of the plate 38 which is, in turn, pressed against the strip 41 that forms a part of the frame 10. The ends of the plate 38 r are knifed, and one end engages the lower end of the strip 41, and the other engages the end of the plate 39 against which it shoulders to permit angular movements of the plates 38 and 39 relative to each other and relative to the strip 41. v

The springs 40 are connected to the ears 42 formed on the strip 41 and the plate 39 and produce pressure components at the joint between the plates and at the movable contact 37 in directions substantially at right angles to the line of direction of the pressure exerted by the springs 40, the plates being yieldingly held in these positions for short, angular movements by the springs 40, as determined by suitable limiting stops and the fixed contacts 43 for limiting the movement of the plates and the movable contact 37.

The switch is opened and closed by the bellows operating through a rod 4'7 to locate the joint .between the plates either above or below the 45 plane of the axes of the springs 40 to produce a corresponding change in' the direction of the lateral components to produce corresponding opening or closing movements of the switch.

. The rod 47 extends through an opening 48 in 56 theplate 38 and has the notches 49 that engageopposite sides of the plate and afiord a short floating movement of the rod and the plate 38 one relative to the other. When the notches 49 are moved to the plane of the axes of the spring 40,

the joint is snapped through the plane of the springs 40 to open or close the switch.

The temperatures at which the switch is closed is adjusted by means of the screw 51 that adjusts the pressure of the spring 52 which counteracts the pressure of the fluid within the bellows. The

spring 52 is located intermediate a flanged disc 53 that engages the rod 47 and an adjusting plate 54 that is adjusted by the screw 51. A knob 55 having a suitable adjustment indicator may be connected to the end of the screw 51 to enable ready adjustment ofthe temperature of the refrigerator by the user in the manner well known in the art.

The switch is responsive not'only to the re- 7 irigerating conditions existing in the apparatus,

but also to the current flow in the circuit of the motor as well as to manual operation for opening and closing the switch at will. In the construction shown, members 65, 66, and 6'7 are provided for positioning the movable contact in the vicinity of the 'fixed contacts in order that the circuit may be opened and closed by the operation of the bellows when the current is normal, or to remove the movable contact to a point remote from the fixed contacts to place the movable contact in safe standing and enable use of the control device for controlling motors and refrigerating apparatus of difierent capacities. The members are interconnected to enable automatic and manual operation of the switch.

The members 65, 66, and 67 extend through an opening formed in the movable plate 39 of the jointed switch arm. The members 65 and 66 extend through the opening 78 located in the base 6 and the opening '79 located in the plate 80. The member 67 extends through the opening 81 in the plate and the opening '78 in the base 6.

The member 65 has a hook 82 adapted to engage a ratchet or ribbed cylinder 83 having a metal sleeve 84 that fits over a rod 85 that is fixedly connected to the base 6. The member 65 is connected to a tension spring 86 that tends to draw the hook against and rotate a ribbed cylinder 83. The rod 85 .protrudes from the sleeve, and a resistance wire 87 is woundaround and spaced from the rod 85. The resistance coil 87 is connected through the switch to the motor circuit whereby flow of an excess current will heat the rod 85, and the rod 85 will transmit the heat into the sleeve 84. The rod 85 is connected to the sleeve 84 by a small quantity of solder of suitable alloy that will melt at a desired predetermined temperature and will immediately solidify when the temperature is reduced. Thus, when a current fiows that is sufiiciently large to melt the solder, the cylinder83 will' be released and consequently will release the member 65 that in turn operates through the other memers 66 l and 6'7 to open the switch.

The member 65 is provided with an ear 88 to which one end of the tension spring 86 is connected. The opposite end of the'spring 86 is connected to the plate 80 at an opening 89 located therein and so as to incline the spring outward to pull the hook against the ribbed cylinder 83 as well as in an upward direction. The edges of the upper end portion of the member 65 are located in the notches 90 formed in the edge. of the opening '79.

The member 66 has a part 91 that is located at right angles to the body part 92 of the member. The part 91 has a lug 93 that projects into a slot 94 formed in the member 65 and so as to be engaged by the end of the slot 94. The slot has a sufficient length to enable free movement of the lug 93 along the slot when the hook 82 of the member 65 is engaged by the ribbed cylinder 83. The edge portions of the part 91 move in the notches 95 formed in the edges of the opening 79. The lug 93 engages the plate 80 in the vicinity of the edge of one of the notches 95 when the member 66 is raised. Consequently, when the member 65 is released, the spring 89 raises the member 65, and the member 66 is raised by the engagement of the lower end of the slot 94 with the lug 93.

The member 67 is interconnected with the member 66 by means of the lug 96 formed on the member 66 and having an edge portion 97 that is inclined to the sides of the end of the member 67 and extends into an opening 105 formed in the end of the member 67 to move the member 67 downwardly. The member 6'] is limited in its downward movement by the shoulder 98s striking the base 6 when depressed by the 67 is depressed substantially as shown in Fig. 1. l

operation of the member 66. The member 67 has a notch or recess 99. The opposed end edges of the notch 99 are located on opposite .sides of the When the member 67 is raised, it locates the movable contact so remote from the fixed contacts that the switch cannot be closed by the operation of the bellows, as shown in Fig. 2. The movable contact of the switch is thus placed in a safe, re-

mote position that enables the use of motors ofdifierent capacities.

The upper end of the member 67 has a pair of I down against the tension of the spring 103. The

end of the member 67 may be displaced laterally to disengage it from the tongue 102'by an upward movement of the member 66. The outwardly inclined edge portion 97 of the lug 96 engages the end 104 of the opening 105 to move the end of the member 67 in a direction away from the member 66 and to disengage the member 67 from the tongue 102. Preferably, the end 104 of the opening 105 has a sloping edge portion which coacts with the edge portion 97 to move the end of the member 67 away from the member 66, whereupon the member 67 and the switch will be drawn upward by the spring 103 to position the movable contact 37 remote from the fixed contacts 43 and prevent closing of the switch by the bellows. The ends of the spring 103 are hooked into the openings 106 of the plate 80, and the ear 107 formed on the member 67. The spring is biased to normally maintain the end of the member 67 in engaging relation with the tongue 102 on the-plate 80.

The members 65 and 67 may be depressed byv the manual operation of the member 66. If the member 65 has been released, the lug 93 of the member 66 engages the end of'the slot 94- to push the member 65 down so that the hook 82 will engage the ribbed cylinder 83, and the lug 96 engages the lower end of the opening 105 until the end of the member 67, by reason 'of the biased relation of thespring 103, engages the tongue 102. The upper end of the member 66 protrudes well above the plate 80, and a knob 108 may be connected to the end of the member,.6 6 for restoring the member 67 when it has been tripped by the operation of the overload latch 65 .or by the manually operable member 66.

When the current through the heat coil 87 f exceeds a predetermined amount, a wide separa tion of the switch contacts is'produced by releasement of ,the member 65 which engages the member 66 that in turn trips the member 67 to cause the close the contacts in response to temperature variation of the refrigerator, means for moving the movable contact member in response to a predetermined overload current, means whereby the contact separation'is limited to one extent when operated in response tmtemperature' variation and to a greater extentwhen opened in response to the overload current.

2. In a switchhaving a pair of contacts, one of them movable relative to the other, a pressure device for operating the switch, a current overload device for operating the switch, and a manual control device for operating the switch, and means for producing a wider separation of one contact from the other contact upon operation of either the current overload device or the manual control device than is produced by the pressure device and preventing closing of the switch by the pressure device.

3. In a switch having a pair of contacts, one of them movable relative to the other, a pressure device for operating the switch, a current overload device for operating the switch, and a manual control device for operating the switch, and means operated by the current overload device or the manual control device and having a part for limiting the closing movements of the switch and for producing a wider separation of one conclose the switch, means for limiting the movementof the movable contact and for shifting the movable contact relative to the fixed contact to permit closing of the switch by the movement of the movable contact produced by the pressure device and to move the movable contact away from the fixed contact to prevent closing of the switch by movement of the movable contact produced by the pressure device.

5. In a switch having a pair of contacts, one of them movable relative to the other, a pressure device for moving the movable contact to open and close the switch, means for limiting the movement of the movable contact and for moving the movable contact relative to the fixed contact to permit closing of the switch by the movement of the movable contact produced by the pressure device and to move the movable contact away from thefixed contact to prevent closing of the switch by movement of the movable contact produced by thepressure device, a currentoverload trip device for operating the said means to displace the said movable contact relative to the fixed contact to prevent closing of the switch until thesaid overload trip device is restored.

6. In a thermic switch, a fixed contact member and a movable contact member, a thermic responsive means for opening the contacts in response to temperature variations of the thermic responsive means, an over-load current operative means for moving the movable contact in response to a predetermined over-load current, means for producing a limited contact separation when the contact is operated by the thermic responsive means and means for producing a wider contact separation when the contact member is operated by the over-load responsive means.

7. In a thermic switch including a movable con- -tact member and a fixed contact member, a -thermo responsive means for opening and closing said switch in response to temperature variations, manually operated means for opening and closing said switch, an over-load current responsive means for opening the said switch upon the flow of a substantially predetermined over-load curtact member and a fixed contact member, a

thermo responsive means for opening and clos ing the said switch in response to temperature variations, an over-load responsive means for opening said switch in response to an over-load current and means for producing a wider separation of the contact members when the switch is open in response to an overload current than when the switch is opened by the said temperature responsive means.

9. A switch having a pair of contacts, one of them movable relative to the other, a thermlc ,device for moving the movable contact to open and close the switchin response to temperature variations, means for limiting the opening movement of the movable contact when operated by the said thermio means and for moving the movable contact away from the fixed contact to prevent closing of the switch by the thermic means, a current over-load device for operating the said means to open the said movable contact and produce a wider separation of the contacts than is produced in the opening movement of the contact member by the operation of the thermic means.

ESTEL c. RANEY. 

